I'll grant it can be a problem for super-heavy "application" websites where every GET is a serious computation. So I'm not surprised gitlab is having problems. They've literally the most bloated and heaviest website I've ever seen. Maybe applications shouldn't be websites.
But this spreading social hysteria, this belief that all non-humans are dangerous and must be blocked is a nerd snipe. It really doesn't apply to most situations. Just running a website as we've always run them, public, and letting all user-agents access, is much less resource intensive than these various "mitigations" people are implementing. Mitigations which end up being worse than the problem itself in terms of preventing actual humans from reading text.